Description

Deserialization of Untrusted Data vulnerability in ThemeREX Group Tantra tantra allows Object Injection.This issue affects Tantra: from n/a through 2.9.0.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-10-10T08:17:05.300Z",
  "pubdate": "2026-10-10T08:17:05.300Z",
  "executiveSummary": "The ThemeREX Group Tantra theme for WordPress contains a critical Deserialization of Untrusted Data vulnerability, allowing for Object Injection. This flaw originates from improper handling of serialized data passed to the application without sufficient validation or integrity checks.\nThe vulnerability affects all versions of the Tantra theme from n/a through 2.9.0. By providing a specially crafted serialized payload, an unauthenticated or authenticated attacker can manipulate PHP objects within the application scope.\nThe impact of this vulnerability is severe, as it can lead to Remote Code Execution (RCE), arbitrary file deletion, or sensitive data access, depending on the availability of 'gadget chains' within the theme or the wider WordPress ecosystem. Successful exploitation allows an attacker to bypass security controls and execute arbitrary logic in the context of the web server process.\nThis vulnerability carries significant risk as it can lead to full site compromise. Remediation is essential for any deployment of the affected versions of the Tantra theme.",
  "technicalDetails": "The root cause of this vulnerability is the use of unsafe PHP deserialization functions (such as unserialize()) on user-supplied input that has not been sanitized or verified for authenticity. When the Tantra theme processes data, it fails to implement a secure deserialization pattern, allowing an attacker to inject serialized strings that represent arbitrary PHP objects.\nThe exploitation flow begins with the attacker identifying an entry point where input is accepted—often through HTTP POST or GET parameters—that is subsequently passed into a vulnerable deserialization function. The attacker crafts a malicious serialized payload containing a serialized object structure.\nWhen the application processes this payload, the PHP interpreter instantiates the object based on the provided class definition. If the application environment contains 'gadget chains'—existing classes with 'magic methods' (such as __destruct(), __wakeup(), or __toString()) that perform dangerous actions like file operations, database queries, or command execution—the attacker can trigger these methods during the object's lifecycle.\nBy chaining these magic methods, an attacker can manipulate the internal state of the application. For instance, if an existing class has a __destruct() method that deletes a file specified by a class property, the attacker can use the deserialization vulnerability to set that property to an arbitrary file path, resulting in unauthorized file deletion. In more severe scenarios, the injected object can be leveraged to achieve Remote Code Execution (RCE) by passing controlled data to functions that invoke system-level commands or include arbitrary files.\nThe vulnerability does not necessarily require the attacker to have administrative privileges, provided the entry point for the serialized input is publicly accessible. The attack occurs at the application layer, interacting directly with the PHP object runtime. Once successful, the post-exploitation impact includes full control over the WordPress instance, potentially leading to unauthorized data exfiltration, defacement, or persistence through the installation of malicious backdoors within the web root."
}